Wireless communications providers strive to provide robust and reliable service to their subscribers. Despite best efforts on the part of the providers, however, providing reliable service in some locations within a service area can be problematic. Service reliability in these locations can be compromised due to, for example, low signal levels, network resource scarcity, and interference introduced by land topology, physical obstructions, a large volume of transient subscribers, and sources of radio interference specific to a given location.
For example, a tall building or other obstruction in an urban area can block the propagation of radio signals, causing an area of low or no signal proximate to the obstruction. Similar issues can be caused by hilly or mountainous terrain. Multipath fading can be caused by reflection of radio waves off of multiple obstructions. Network resource scarcity can be caused by an abnormally large numbers of transient subscribers entering an area, or an inability on the part of the service provider to add additional resources due to legal and/or technical reasons (such as, for example, legal hurdles to building a new base station/cellular tower).
Locations where low performance may be experienced by a subscriber are referred to generally herein as “dead zones”, and can also be referred to as “coverage holes”, or “no-service areas”. Wireless providers attempt to minimize these areas, but often there are still locations in a coverage area where a subscriber may experience dropped calls or other access failures. As used herein, a dropped call is an unexpected termination of a voice call due to technical reasons. Although these problematic locations are generally isolated pockets within a larger service area, subscribers attempting to access the network in these locations can find the user experience to be less than optimal